Quote from Smex on the 10th of March 2016:
To Team exile,
Can someone please add xAUx members to uplay for tonights match.
Haven't had a reply back yet
If they aren't replying in a pm I don't think they will see a forum thread...unless they are dodging a match or whatever the case may be, regardless if they don't turn up, free win for you unless you are that keen to play them, then in that case message a admin (preferably a rainbow six siege admin) and ask if they can reschedule the match...or even better, open a support ticket to the correct admin team and they will see what they can do (about rescheduling of course)